1. Field of the Invention
The present invention relates to novel 2-(indenyloxymethyl)-morpholine derivatives and more particularly it relates to 2-(indenyloxymethyl) morpholine derivatives possessing excellent methamphetamine stereotyped increasing and antireserpine activities which are desirable properties for antidepression agents.
2. Description of the Prior Art
As an antidepression agent having a morpholine ring, there are known the compounds as described in, for example, U.S. Pat. No. 3,714,161 (British Pat. No. 1,138,405; Belgian Pat. No. 708,557; Canadian Pat. No. 860,341; Australian Pat. No. 6,730,109; Swiss Pat. Nos. 504,452 and 513,904; French Pat. No. 1,571,341; French Medical Specific Pat. No. 7557, etc.,) and U.S. Pat. No. 3,712,890 (British Pat. No. 1,260,886; Canadian Pat. No. 913,090; Swiss Pat. No. 539,068; etc.).
The compound which is believed to possess the highest activity among the compounds disclosed in the aforementioned patents is 2-(2-ethoxyphenoxymethyl) morpholine which is generally known as Viloxazine (see Nature, 238, 157-158 (1972)). A series of investigations made by K. B. Mallion, A. H. Todd, R. W. Turner, et al who are the inventors of Viloxazine suggest the relation between the chemical structures and the pharmacological activities thereof. That is, it is preferred that the compound has one substituent at the 2-position of a phenoxy group bonded to morpholine. Furthermore, when the phenoxy group forms a fused ring, it is preferred that, for example, a tetralin-type ring is formed by the condensation of a tetramethylene group. However, when the condensed ring forms an indane-type ring by the condensation of a trimethylene group, the pharmacological effect is diminished.